Re: recovery_target_action = pause & hot_standby = off

On 15/03/15 14:51, Magnus Hagander wrote:
> On Sun, Mar 15, 2015 at 2:27 PM, Andres Freund <andres(at)2ndquadrant(dot)com
> <mailto:andres(at)2ndquadrant(dot)com>> wrote:
>
> On 2015-03-12 15:52:02 +0100, Andres Freund wrote:
> > /*
> > * Override any inconsistent requests. Not that this is a
> change
> > * of behaviour in 9.5; prior to this we simply ignored a
> request
> > * to pause if hot_standby = off, which was surprising
> behaviour.
> > */
> > if (recoveryTargetAction == RECOVERY_TARGET_ACTION_PAUSE &&
> > recoveryTargetActionSet &&
> > standbyState == STANDBY_DISABLED)
> > recoveryTargetAction = RECOVERY_TARGET_ACTION_SHUTDOWN;
>
> While it's easy enough to fix I rather dislike the whole intent here
> though. *Silently* switching the mode of operation in a rather
> significant way seems like a bad idea to me. At the very least we need
> to emit a LOG message about this; but I think it'd be much better to
> error out instead.
>
> <9.5's behaviour was already quite surprising. But changing things to a
> different surprising behaviour seems like a bad idea.
>
>
> +1. Especially for "sensitive" operations like this, having
> predictable-behavior-or-error is usually the best choice.
>

Thinking about it again now, it does seem that ignoring user setting
because it's in conflict with another user setting is a bad idea and I
think we in general throw errors on those.

So +1 from me also.

--
Petr Jelinek http://www.2ndQuadrant.com/
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